DISINFECTION 329 



drying apparatus. A central chamber receives the articles 

 to be disinfected, and is surrounded by a boiler containing 

 a solution of calcium chloride at a temperature of 225 F. 

 This is heated by a small furnace, and the steam given off 

 (218-300 F.) is conducted into the central chamber. The 

 steam is not confined under any pressure except that of the 

 atmosphere. When the steam has passed for a sufficient 

 length of time, it is readily diverted into the open air. Hot 

 air is now introduced, and at the expiration of an hour the 

 articles may be taken out disinfected and as dry as they were 

 when inserted. The apparatus is comparatively inexpens- 

 ive, and not of a complicated nature. The current steam 

 is saturated, and at a temperature a few degrees above the 

 boiling-point. Many experiments have been performed 

 with this apparatus, and there is now a large amount of 

 evidence in favour of it and current steam disinfection. 



Reck' s apparatus is another kind of saturated steam disin- 

 fector, which resembles the Equifex, but differs from it in 

 employing steam as a current. 



It is probable that many other forms of steam disinfector 

 will be invented, and each will have its enthusiastic sup- 

 porters. Even at the time of writing some excellent results 

 are announced from America. 



2. The effects of chemical substances as solutions, or in 

 spray form, upon bacteria have been observed from the 

 earliest days of bacteriology. To some decomposing matter 

 or solution a disinfectant was added and sub-cultures made. 

 If bacteria continued to develop, the disinfection had not 

 been efficient; if, on the other hand, the sub-culture re- 

 mained sterile, disinfection had been complete. From such 

 rough-and-ready methods large deductions were drawn, and 

 it is hardly too much to say that no branch of bacteriology 

 contains such a vast mass of unassimilated and unassimilable 

 statements as that relating to research into disinfectants. 

 Most of the tabulated and recorded results are conspicuous 



